In integrated circuit manufacturing, wire bonding is a well proven method used to connect a semiconductor die having electrical circuitry to a pin on a component package. Also, in integrated circuit manufacturing, it is becoming increasingly common to package multiple semiconductor die in a single package, where the multiple semiconductor die can be in a stacked configuration. Within integrated circuit manufacturing it is also a common practice to test the functionality of the semiconductor die before completing component assembly. “Probe test” is one such method used to test a semiconductor where a probe contact is commonly used as a mechanical and electrical interface to bond pads on the die.
One problem with using a mechanical interface, for example, a probe needle, is that the bond pads may be damaged or contaminated, preventing a reliable electrical connection between the bond pad and the package pin when the die is wire bonded. This problem is made worse by the decreasing bond pad geometries characteristic of modern deep sub-micron semiconductor technology. Decreasing bond pad geometries include smaller bond pads on which smaller wire bonds are formed. This increases quality and reliability concerns for bond pads that have been damaged by a probe contact. As the bond pad size decreases, the ratio of the damage caused by a probe contact to the bond pad area increases. Another problem with the shrinking bond pad geometries is that the spacing between the bond pads can be too small for robust probe testing using traditional methods such as cantilever probe needles.
Thus, there is a need for the ability to probe test a die without causing unreliable wire bond connections, and to ensure a robust probe test on die with small bond pads and fine pitch spacing of the bond pads. There is also a need for the ability to provide electrical connections to multiple die within a single package. And in many cases, there is a need to meet the preceding criteria without affecting die size significantly to keep costs down.